Expandable compositions and methods of making and using the compositions

ABSTRACT

A novel expandable composition and method for using the same are disclosed. The disclosed method relates to using the composition, for example, as an automotive cavity sealant. The inventive composition normally is a combination of at least one base polymer, at least one expansion or blowing agents, at least one hydrocarbon resin, at least one curing agent or catalyst and optionally at least one additives such as a supplemental polymer, colorant, tackifier, processing oil, among others.

The subject matter herein claims benefit of prior filed U.S. patentapplication Ser. Nos. 60/161,528, filed on Oct. 26, 1999 and 60/219,095,filed on Jul. 18, 2000; the disclosure of which is hereby incorporatedby reference.

FIELD OF THE INVENTION

The instant invention relates to a novel expandable composition. Theinstant invention also relates to a method of using the composition, forexample, as an automotive cavity sealant.

BACKGROUND OF THE INVENTION

Expandable sealants are known in this art such as described in U.S. Pat.Nos. 4,427,481; 4,874,650; 5,266,133; 5,373,027; 5,506,025; 5,266,133;5,373,027; and 5,678,826; and European Patent No. EP 0 730 998B1; thedisclosure of each of which is hereby incorporated by reference. Oneconventional cavity sealing arrangement and method is described in U.S.Pat. No.5,040,803; the disclosure of which is also hereby incorporatedby reference. Other convention cavity sealants comprise polyvinylchloride (PVC) based materials that are pumped into location and, insome cases, expand after being exposed to a sufficient amount of heat.Conventional sealants also include polyurethane based or containingfoams. Typically, these sealants are employed in automotive applicationsfor filing cavities, stiffening adjacent components and dampeningsound/vibrations.

Conventional sealant compositions may be limited in their applicationdue to the temperature and time required to cause the sealant to expand.Certain conventional compositions also require the addition of heat toproduce the expandable composition as well as to cause the compositionto expand. There is a need in this art for an expandable compositionthat: 1) is activated at a relatively low temperature, 2) adheres to ametal substrate, 3) is easily installed and remains in a predeterminedlocation and 4) for some applications is resistant to fuel, e.g., dieseland gasoline.

SUMMARY OF THE INVENTION

The instant invention solves problems associated with conventionalsealants and methods by providing a novel composition that can be moldedinto a predetermined shape and expanded by being exposed to a sufficientamount of heat, e.g., an external source of heat. In contrast toconventional sealants, the inventive composition can: 1) have apredetermined shape, e.g., by injection molding, 2) located, e.g.,within a cavity, or around or upon a member to be sealed, prior to/postassembly while remaining in a predetermined location, 3) employed in awide range of applications, 4) produced at relatively low temperatures;5) expanded at relatively low temperatures, e.g, after being installedwithin a cavity; and 6) recycled as scrap material post cure.

The inventive composition may be employed in automotive applications,e.g., the composition may be used in accordance with the guidelines setforth in Ford Specification No. ESB-M 18P11 A, WSB-M 18P11A2, GeneralMotors Specification No. 9984188 C/D/G and DaimlerChrysler SpecificationNo. MS-CD 627 B/E, 644, and 466; the disclosure of these Specificationsis hereby incorporated by reference.

By tailoring the inventive composition, the expansion initiationtemperature of the composition, degree of expansion, time until fullyexpanded, among other processing characteristics, can be predeterminedto satisfy a wide range of end-uses. The inventive composition canexpand about 450 to about 800 volume % at temperatures of about 250 toabout 375 F (adjacent metal temperature), depending upon thecharacteristics of the composition. When the heat of expansion isprovided from a powder coat system, the temperature can be 385 F toabout 400 F. For example, the inventive composition can expand at leastabout 500% at a temperature of about 300 F. Depending upon the desiredexpansion rate and expansion initiation temperature, the inventivecomposition can be tailored to expand 800 to 1,000% and have expansioninitiation temperatures from about 120 to 170 C (adjacent metaltemperature).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is an end-view of a cross-section of one aspect of the instantinvention.

FIG. 1B is a side-view of the product illustrated in FIG. 1A.

FIG. 2A is an end-view of a cross-section of another aspect of theinstant invention.

FIG. 2B is a side-view of the product illustrated in FIG. 2A.

FIG. 3A is a first side-view of a further aspect of the instantinvention that includes a fastener for use in sealing an automotiveA-pillar.

FIG. 3B is a second side-view of the product illustrated in FIG. 3A.

FIG. 3C is an end-view of the product illustrated in FIG. 3A.

FIG. 4A is a first side-view of a further aspect of the instantinvention that includes a fastener for use in sealing an automotivefront B-pillar.

FIG. 4B is a second side-view of the product illustrated in FIG. 4A.

FIG. 4C is an end-view of the product illustrated in FIG. 4A.

FIG. 5A is a first side-view of a further aspect of the instantinvention that includes a fastener for use in sealing an automotiveC-pillar.

FIG. 5B is a second side-view of the product illustrated in FIG. 5A.

FIG. 5C is an end-view of the product illustrated in FIG. 5A.

FIG. 6 is an overhead view of a further aspect of the instant inventionthat can be compression fit within a cavity.

DETAILED DESCRIPTION

The inventive composition broadly comprises a combination of at leastone base polymer, at least one expansion or blowing agents, at least onehydrocarbon resin, at least one curing agent or catalyst and optionallyat least one additives such as a supplemental polymer, colorant,tackifier, processing oil, among others.

While any suitable base polymer or mixtures thereof can be employed, anexamples of suitable polymers comprise at least one member from thegroup of styrene butadiene rubber, a modified ethylene copolymer blendsuch as maleic anhydride modified copolymer of ethylene and vinylacetate, among others. Such polymers are available commercially asBynel™ CXA 3860 (supplied by The DuPont Company, Wilmington, Del.).Normally, the base polymer corresponds to about 55 to about 84 wt. % ofthe composition prior to expansion. When a fuel resistant composition isdesired, a base polymer can comprise at least one member selected fromthe group consisting of epoxies, epoxy functional compounds, modifiedpolyethylene blends, mixtures thereof, among others.

Any suitable expansion or blowing agent can be employed that becomes orgenerates a gaseous or vapor phase (e.g., nitrogen, carbon dioxide,etc.), when exposed to a sufficient amount of heat. Examples of suchexpansion agents comprise at least one of azodicarbonamides andp,p′-oxybis(benzene-sulfonyl hydrazide) ordiphenylozide-4,4′-disulphohydrazides supplied, respectively, byUniroyal as Celogen™ 765 and Celogen™ OT. Typically, the expansion agentcomprises about 1 to about 15 wt. % of the composition prior toexpansion. The amount of expansion agent can be tailored depending uponthe temperature/time, desired degree of expansion, time permitted forexpansion, among other parameters. Generally, higher concentrations ofCelogen™ OT are employed in conjunction with urea (e.g., BIK OT suppliedby Uniroyal Chemical Company) for relatively low temperature expansionwhereas Celogen™ 765 accommodates higher temperature expansion.

In some cases, the expansion or blowing agent has been treated. Bytreated it is meant that the expansion or blowing agent has beencontacted or admixed with a suitable binder, e.g, binder comprising atleast one of napthenic, glycerins, polyols, ethylene propylene monomer,paraffinic, among others. For example, an expansion agent comprisingCelogen™ OT has been admixed with a naphtheninc binder for safety anddespersion. Examples of suitable binders comprise those commerciallysupplied by Polychem, PPD celot 90, ElastoChem, OT-72 AkroChem, andmixtures thereof. The ratio of expansion agent to binder normally rangesfrom about 5 to about 30%. Notwithstanding the binder the expansionagent is typically at least about 90% active.

Moreover, the expansion or blowing agent can be encapsulated within ashell. That is, a liquid or gaseous blowing agent is combined with orencapsulated within a thermoplastic particle or powder, e.g., ahydrocarbon encapsulated within an acrylonitrile shell as in Expancel®that is supplied by Expancel Inc., a division of Akzo Nobel Industries.For example, the shells can be fabricated from polyolefins such aspolyethylene and polypropylene; vinyls, EVA, nylon, acrylics, amongother materials. The shells are selected to melt, soften, expand,rupture or retain their physical configuration depending upon whether ornot an open or a closed cell expanded material is desired. The shellscan also comprise a distribution of differing particle sizes,composition and activation temperatures, e.g., a foam precursorcomprising at least two different particle sizes and activationtemperatures. Specific examples of suitable encapsulated blowing agentscomprise at least one member selected from the group of hydrocarbonssuch as isobutane and isopentane; fluorocarbons such as1-1dichloroethene, HFC-134a, HFC-152a; and nitrogen releasing chemicalblowing agents such as those supplied as Celogen® by UniRoyal that areencapsulated within any suitable thermoplastic, e.g., 2-methyl2-propenioc acid methyl ester polymer with 2-propenenitrile andvinylidene chloride polymer and polyvinylidene fluoride. These materialsare supplied commercially by Expancel, Inc., a division of Akzo Nobel asExpancels® 051WU, 051DU, 091DU80, 820WU, 820DU, 642WU, 551WU, 551WU80,461DU or Micropearl® F30D supplied by Pierce and Stevens. Thesematerials can be supplied in either dry or wet form. These materials canalso be coated with any suitable material for controlling the activationtemperature of the encapsulated blowing agents. An example of a coatingcomprises an acrylated materials, waxes, among other materials.Depending upon the physical characteristics desired in the foam, theshells can be used to obtain open or closed cells.

The inventive composition can comprise any suitable hydrocarbon resin ormixtures thereof that accommodates the expansion temperature, e.g, atleast about 300 F. Examples of suitable resins are rosin esters,polyterpenes, an aliphatic or aromatic hydrocarbon resins, e.g, C5 to C9hydrocarbon and aromatically modified hydrocarbon resins, mixturesthereof, among others. Suitable resins are available commercially asPiccotac® supplied by Hercules Incorporated, Wilmington, Del. orEscorez® supplied by Exxon Chemical Co., Houston, Tex., Zonester® byArizona Chemicals, and Wingtac® by Goodyear. Normally, for best results,the hydrocarbon resin can be crushed or ground to form a particulatematerial, e.g., the particle size normally pass through 80% at 40 meshand 100% at 30 mesh. The hydrocarbon resin can comprise or consistessentially of about 1 to about 15 wt. % of the inventive compositionprior to expansion.

The inventive composition normally comprises at least one curing agentor catalyst such as tetramethylthiuram disulfide, e.g., TMTD applied byAkrochem Corporation, Akron, Ohio, organic peroxide by AkroChem, andurea or urea modified materials (e.g., surface treated), e.g., BIK-OT byUniroyal Chemical Company. Without wishing to be bound by any theory orexplanation, it is believed that the catalyst functions as a source ofsulfur and enhances the quality of the fine closed cells in the expandedproduct. The amount of curing agent typically corresponds to about 0 toabout 5 wt. % of the composition prior to expansion.

The inventive composition can also comprise at least one supplementalpolymers. An example of a suitable supplemental polymer comprisespolybutadiene rubber, ethyl vinyl acetate, ethylene propylene dienemonomer (EPDM), ethylene-acrylic acid polymer such as Primacor™ 5990polymer supplied by The Dow Chemical Company, Midland, Mich. The amountof optional supplemental polymer normally corresponds to about 5 toabout 10 wt. % of the composition.

Further, the composition can also comprise at least one additive such asa colorant, tackifier, filler, plasticizer, processing oil,antimicrobial agents, UV curing agents, magnetic/magnetisable materials,among others. One suitable additive comprises EPDM. While any desirablecolorant can be added to the composition, green or blue colorantsupplied by Akron Chemical Company, Akron, Ohio as Akrochem 626 and 633powder are effective. The total amount of additives, if present,corresponds to about 0 to about 5.0 wt. % of the composition beforeexpansion. Virtually any additive can be added so long as the additivedoes not adversely impact the processability or expanded compositioncharacteristics. In some cases for ease of handling, additives to theinventive composition (e.g., colorant, tackifier, filler, plasticizer,processing oil, antimicrobial agents, among others), are blended intopellets and subsequently combined with the remaining components of theinventive composition.

While the presence of ionomeric compounds does not adversely impact theutility of the inventive composition, in one aspect of the invention thecomposition can be substantially free of ionomeric compounds. By“substantially free” it is meant that the composition has less thanabout 20 parts or 5.5 wt. % of ionomeric compounds, e.g., usually about0 wt. % of ionomers. Examples of such ionomeric compounds that may beobviated by the instant invention are disclosed in the aforementionedU.S. Pat. No. 5,266,133. The ability to obviate ionomeric compoundsreduces cost of the composition as well as enhances processability.

The inventive composition can be produced by mixing the components inany suitable apparatus, e.g., a dispersion mixer or twin screw, orcontinuous mixer. With the exception of the optional processingoil/plasticizers, the components of the inventive composition are solidsunder ambient conditions. Once mixed, the combination can be shaped byemploying any expedient method such as blow molding, injection molding,compression molding, die cutting, extrusion, among other methods.Depending upon the configuration of the shaped inventive composition,normally injection molding or extrusion is preferred. For example, theinventive composition can be fabricated to possess the configuration ofFIGS. 1A and 1B (described below in greater detail) by employing asingle cavity injection mold, or a single cavity profile extruder.Injection molding can employ a Toyo Model TM200 molding machine with awater jacket around the barrel set at about 160 F, a mold temperatureset at about 70 F, and a cycle time of approximately 30 seconds.Extrusion can employ conventional equipment and extrude a length ofmaterial having the same cross-section as an injection molded component.When extruding, the length of the material can be continuous and thencut at suitable increments, e.g., four (4) inch increments. An exampleof a conventional extruder comprises a 12/1 extruder with a standardflight screw, with a feed rate of about 150 lbs/hr, 160 F feedtemperature, 200 F barrel temperature, and 200 F profile extrusiontemperature. Normally, the extruded profile is immediately cooled by achilled water bath to help maintain its shape. The extruded profile canpossess any suitable configuration such as a circle, oval, square,pentagon, curvilinear shapes, among others.

The inventive composition can be shaped into a two or three dimensionalconfiguration, or pumped to a location prior to expansion. For example,the composition can be injection molded into a hollow or solidcylindrical shape that is in turn located within an automotive cavityduring assembly, e.g., formed reinforcement tubes/channels, rocker panelor pillar cavities, among other areas/cavities. After being properlypositioned (e.g., within an automotive cavity), the composition expandswhen exposed to the relatively high temperatures employed in subsequentprocessing, e.g., bake cyles, electrodeposition, painting, among otherassembly procedures.

The inventive composition can be associated with or adhered to avirtually unlimited array of substrates such as electrocoated surfaces,e.g., panels including automotive components, cold rolled steel,galvanized surfaces, galvanel surfaces, galvalum, galfan, among others.The substrate or surface that contacts the inventive composition canalso comprise a painted surface, ceramic, glass, thermoplastic,thermosets, among others.

In one aspect of the invention, the inventive composition is employed asa component of a composite structure. That is, the composition can belocated or sandwiched between at least two metal layers thereby forminga so-called constraint layer damper. The composition may also be shapedinto a thin-walled article having a continuous surface and at least oneinternal cavity. The composition can also be shaped to produce thearticles disclosed in U.S. Pat. No. 5,678,826.

In another aspect, the instant invention relates to an expandablematerial having a predetermined configuration or shape. In particularthe expandable material can be configured into a shape that retains theexpandable material at or within a defined location, e.g., an expandablematerial comprising an acoustical material located within an automotivecavity. The expandable material can be shaped so as to beself-retaining. By “self-retaining” it is meant that the expandablematerial after being placed in a defined location andposition/orientation maintains the placement for a predetermined lengthof time (e.g., until being heated to expand) without utilizingseparately applied fasteners. Self-retaining properties can achieved byshaping the expandable material into a clip, wedge, strap, bolt, amongother shapes designed to mechanically maintain the expandable materialat a predetermined placement. The self-retaining properties can also beachieved by compression fitting. While the self-retaining expandablematerial can be produced from any suitable composition, the compositiondisclosed herein is particularly useful. For example, a self-retainingexpandable can be formed from the inventive composition such that theexpandable material has a unitary structure that includes a fastener.That is, the fastener would function to retain the expandable materialin a predetermined location and expand (upon heating) to assist insealing. The unity self-retaining structure can be tailored to have aconfiguration including an integral fastener for a specific area, voidor cavity to be sealed.

In a further aspect, the instant invention relates to an expandablematerial having a predetermined shape or configuration and having atleast one fastener that retains the expandable material at apredetermined location. The fastener can maintain the fastener at anysuitable predetermined location such as an automotive front and/or rear“A”-pillar, “B”-pillars, “C”-pillar, among other locations where it isdesirable to position an expandable material adjacent to a member to besealed. By “adjacent” it is meant term “adjacent” as used in thisspecification and the claims, unless expressly stated otherwise, meanstwo components that are in contact with each other, are next to eachother with a space separating them, or are next to each other with athird component in between. By “member to be sealed” it is meant thatthe material contacts the member either prior to, during or aftercompleting expansion. The member to be sealed can be at least partiallyembedded or penetrated by the expanding material. The fastener can beattached to or incorporated within the material prior to expansion.While any suitable fastener can be employed, examples of suitablefasteners comprise at least one member selected from the group ofblades, pins, push-pins, clips, compression fit fasteners, among otherfasteners that are capable for maintaining a shaped expandablecomposition in a predetermined location without adversely affecting theexpansion or performance of the composition. Specific examples ofsuitable fasteners are described in aforementioned U.S. Pat. Nos.5,040,803 and 5,678,826.

Certain aspects of the invention are better understood when referring tothe Drawings. Referring now to the Drawings, FIG. 1A illustrates anexpandable material 10 of the instant invention. The expandable materialpossesses a circular gripping area 11. The portion 12 of material 10that is adjacent to an opening in the circular gripping area 11 canfunction to improve the durability of the material 10 and/or provideincreased material for subsequent expansion. The expandable material 10is retained or clipped around a first automotive member (not shown)having a generally circular cross-section. The expandable material 10generates a sufficient compressive strength to maintain the material ata predetermined location. The portion 13 of material 10 defines anopening 14. The width 15 of opening 14 is greater than or equal to thedistance between a first automotive member within area 11 and a secondautomotive member (not shown) in contact with portion 12′ and 12″. Thisdistance permits the material to grip the first automotive member whilealso being compressed between the first and second automotive members.The length 16 of opening 14 causes or is sufficient to provide a volumeof expandable material between the first automotive member and thesecond automotive member, and to add strength to the gripping action ofarea 11. The length of 16 will increase or decrease as the diameter of11 increases or decreases, respectively. The material can possess a widerange of dimensions; however, normally, the wall thickness shown atportion 17 is about 2 to about 4 mm, dimension 14 about 2 to about 4 mm,the dimension 16 about 25 to about 35 mm and the overall length of 10about 25 to about 45. When the expandable material is obtained byextrusion the length of 16 can be greater than 20 mm.

When the material is exposed to sufficient heat (e.g., about 250 toabout 375 F), the aforementioned expansion agent causes substantiallyall of the material to increase in volume and bond to adjoiningsurfaces, e.g, metal surfaces. While the material illustrated in FIG. 1Ais intended to contact an automotive door intrusion beam and theinterior surface of the door, the composition can also be shaped for useas a sound damper/absorber in an “A” pillar, rear trunk sealant, amongother areas in an automobile for use in controlling sound, water, windand dust.

Referring now to FIG. 1B, FIG. 1B illustrates the expandable materialillustrated in FIG. 1B in cross-section format. While the compositionshown in FIG. 2 is intended to be affixed to a beam having a circularcross-section, the composition can be employed with beams or membershaving a virtually unlimited array of cross-sections. The compositionalso can be molded into a wide variety of shapes, e.g., strips, rods,curvilinear, among others, and sizes.

Referring now to FIG. 2A, FIG. 2A illustrates an expandable materialhaving a similar configuration to that illustrated in FIGS. 1A and 1Bexcept that the expandable material 20 has an enclosed gripping area 21.The expandable material illustrated in FIG. 2A is configured such thatthe material can be inserted onto another member, e.g., a circularcross-section intrusion beam. Gripping area 21 includes protuberances 22that are compressed when another member, e.g,. a pipe, is insertedthrough material 20. By compressing protuberances 22, friction iscreated between the protuberances and the outer surface of the insertedmember and thereby functioning to maintained material 20 at a fixedlocation upon the member.

Material 20 can define at least one slot or groove 23. These slots orgrooves 23 provide locations where the material 20 can be compressed orbent. The ability to bend the material 20 permits locating the materialat a given location without breaking or cracking the material.

Protuberances 22 can possess any suitable configuration. One suchconfiguration is illustrated in FIG. 2B. Referring now to FIG. 2B, FIG.2B illustrates the expandable material illustrated in FIG. 2A incross-section format. The end of protuberance 22 has a radius 24 thatterminates at each end of the opening or hole 25 defined within material20. The terminating radius permits more expedient insertion of a memberinto or through material 20.

Referring now to FIGS. 3A-3C, FIGS. 3A-3C illustrate a further aspect ofthe invention wherein an automotive sealant comprises an integralfastener that is employed for maintaining the inventive expandablecomposition in a predetermined position, e.g., self-retaining.Expandable material 30 having a integral clip type fastener 31 (alsocomprising the inventive expandable material) that maintains material 30adjacent to and within an automotive A-pillar (not shown). Fastener 31also includes a leg or protuberance 32 that extends into the A-pillar.Material 30 defines openings 33 and 34. These openings can be employedfor reducing mass (and material costs), enhancing flow of heat throughthe expandable material (thereby ensuring uniform expansion and loweractivation temperature) and permitting fluids to flow through thematerial (e.g., automotive e-coat, metal treatments, among otherfluids). Material 30 comprises extensions 35 and 36 that extend along anexterior surface of the A-pillar. The material 30 is attached to anA-pillar by inserting fastener 31/32 into the A-pillar such thatextensions 35 and 36 contact the exterior surface of the A-pillar. Thedistance shown by 37 corresponds to the thickness of the A-pillar. Whenmaterial 30 is exposed to an adequate amount of heat, all of material 30(including fastener 31 and extensions 35/36) expands thereby sealing theA-pillar.

Referring now to FIGS. 4A-4C, FIGS. 4A-4C illustrate an expandablematerial having a similar configuration to that illustrated in FIGS.3A-3C except that the expandable material 40 includes an expandable cliptype fastener 41 that is oriented toward extension 42. Material 40defines an opening 43 that functions in the manner described above inconnection with openings 33/34. While material 40 can be employed for awide range of end-uses, material 40 is particularly suited for sealingan automotive front B-pillar.

Referring now to FIGS. 5A-5C, FIGS. 5A-5C illustrate an expandablematerial having a similar configuration to that illustrated in FIGS.3A-4C except that material 50 includes an expandable fastener 51,protuberance 52, opening 53 and extension 54. Material 50, similar tothe materials illustrated in FIGS. 1-4 can be injection molded, can befabricated into a wide range of configurations. The particularconfiguration illustrated in FIGS. 5A-5C is especially suited forsealing an automotive C-pillar.

Referring now to FIG. 6, FIG. 6 illustrates a self-retaining expandablematerial 60 that employs compression fitting. Material 60 comprisesshank portion 61, compressible side portions 62 and 63 and end 64.Material 60 can be inserted into a desired location (e.g., within acavity), by manually gripping shank portion 61 and inserting end 64 intothe location until at least one of side portions 62 and 63 arecompressed towards shank 64. Side portions 62 and/or 63 retain material60 in a self-retained position. If desired, shank portion 61 can haveembossed markings that can be used for gauging the depth that thematerial 60 has been inserted into a cavity.

If desired, the composition can incorporate a reinforcing member.Examples of such reinforcing members comprise glass mesh, mats, plasticor nylon supports, among other materials capable of surviving theexpansion temperature and enhancing the structural integrity of eitherthe unexpanded or expanded composition.

In addition, at least a portion of the inventive composition can belaminated with a film, foil, web, sheet, among others. The laminate canbe a temporary component of the composition such as a release filmand/or permanently in contact with the composition. While any suitablelaminate can be employed, examples of such laminates are disclosed inU.S. Pat. Nos. 4,803,104 and 6,030,701; the disclosure of which arehereby incorporated by reference.

While the above Description emphasizes expandable compositions for usein automotive applications, the inventive composition can be employed ina virtually unlimited array of applications. Examples of suchapplications can include one or more of sealants for aircraft, golfcars, agricultural equipment, marine vessels, an insulating member, aresidential or industrial sealant, among other applications. Theinventive compositions can be extruded, pumped into a desired location,sprayed, preformed (e.g., injection molded), among other methods forusing sealants.

The following Examples are provided to illustrate not limit the scope ofthe invention as defined by the appended claims. The percentages inthese Examples are weight percent (%).

EXAMPLE 1

A composition was prepared by combining 100 parts per hundred resin(phr) of base polymer (Bynel™ 3860 supplied by the DuPont Company), 1.5phr of hydrocarbon based process oil (Tufflo® 500 WsChem-Hall Inc.), 6.7phr of Piccotac® hydrocarbon resin, 0.7 phr pounds TMTD™ supplied byAkroChem, and 10 phr of expansion agent (6.7 phr of Celogen OT and 3.3phr of Celogen 765). 0-1 phr of peroxide supplied by Akrochem.

EXAMPLE 2

A composition was prepared by combining 100 phr of base polymer (Bynel™3860 supplied by the DuPont Company), 20 phr ethylene copolymer(Primacor 5990 supplied by Dow Chemical), 12 phr of expansion agent (8phr of Celogen OT and 4 phr of Celogen 765), 8 phr of hydrocarbon resinand 0.8 phr TMTD™ (supplied by AkroChem), and 5 pounds BIK-OT (suppliedby Uniroyal Chemical Company). 0-1 phr of peroxide supplied by Akrochem.

EXAMPLE 3

A composition substantially the same as that disclosed by Example 2 wasprepared with the exception that 0.04 phr of colorant (supplied byAkroChem) was added.

EXAMPLE 4

The composition of Examples 1-3 were prepared by admixing the basepolymer and, if present, 14% supplemental polymer (Primacor™ ethyleneacrylic acid polymer) together in a Baker-Perkin dispersion mixer. About3.5 pounds (0.97%) of the aforementioned light processing oil was addedto the mixer and mixed for 5 to 10 minutes. The 0-2% curing agent (TMTD™tetramethylthiuram disulfide) and expansion agent (Celogen™ 765) wereadded to the mixer, and the combination was mixed for 3 to 5 minutes.The remaining processing oil was added and mixing continued for 3-5minutes. A blue colorant and additional expansion agent (Celogen™ OT)were added to the mixer and mixed for 3 to 10 minutes.

The aforementioned expansion agents had been pre-treated with 10-28%naphtheninic binder supplied by Polychem or ElastoChem. The pre-treatedexpansion agents possessed at least about 90% of the activity ofuntreated expansion agents.

The mixed composition comprised pellets or particulate of base polymersubstantially uniformly coated. The composition has no reportabledusting characteristics.

EXAMPLE 5

The compositions of Example 4 are dispensed into 5 gallon to 500 poundcontainers. The composition is then shaped by being injection molded ina Boy 30 Ton or Toyo Model No. TM200 injection molding apparatus to forman injection molded part. The injection molded or extruded article isbaked at a temperature of about 300 to 400 F. The baking in turn causesthe expansion agent within the article to become active therebyexpanding the article's volume by at least 600%.

EXAMPLE 6

The compositions of Example 4 are dispensed into an extruder. Thecomposition is extruded to form a sheet structure. The composition isextruded by a 12/1 extruder that has been modified to include acompression flight screw. The following outlines the extrusionparameters: 180 lbs/hr feed rate, 160 F feed temperature, 200 Fcompression section temperature; and 220 F head/die temperature. Theextruded article is expanded by being heated.

EXAMPLE 7

Example 2 was repeated with the exception that ethylene copolymer wasreplaced with 8-20 phr of polybutadiene polymer. The polybutadiene wassupplied by JSR Corp.

EXAMPLE 8

This Example describes making an injection molded composition that wasemployed as a stiffener on an intrusion beam within an automotivepassenger door. The components of the composition are listed in thefollowing Table. TABLE Supplier Material Phr Ameripol-Synpol SBR rubber100 Petrolite Process Aid 87.5 Exxon Hydrocarbon resin 6.3 DuPont EVAresin 300 Polychem Blowing agent 21.8 Atochem Peroxide 6.3 Akrochem TMTD6.3 Cabot Carbon Black 1.9 Mozel Filler 100

The heat expandable composition was mixed in a lab BakerPerkinsdispersion blade. The mixed composition was injection molded into asingle cavity mold having the shape substantially as illustrated inFIGS. 1A and 1B.

The injection molded article was located or clipped about an intrusionbeam. The beam was introduced into a forced air oven chamber and exposedto a temperature of about 325 F for a period of twenty minutes. Thecomposition expanded between the beam and an adjacent steel member (thatrepresented the interior portion of an automotive door skin). Thecomposition adhered to the interior portion of the door skin as well asthe intrusion beam thereby reducing panel mobility. By reducing panelmobility the inventive composition reduces noise caused by rattles,improves strength of the door, among other desirable properties.

Examples 9-11 demonstrate injection moldable compositions that were 5fabricated in accordance with the method of Example 8.

EXAMPLE 9

TRADE NAME COMPONENT AMOUNT Bynel 3860 Maleic anhydride modified 100phr  copolymer of ethylene and vinyl acetate Picotac B Hydrocarbon resin6.7 phr Tufflo 500 Hydrocarbon process oil 1.5 phr TMTDTetramethylthiuram 0.7 phr disulfide Celogen OT Hydrazide expansionagent 6.7 phr Celogen 765 Expansion agent 3.3 phr

EXAMPLE 10

TRADE NAME COMPONENT AMOUNT Bynel 3860 Maleic anhydride modified 100 phrCopolymer of ethylene and vinyl acetate Primacore 5990 Acid mod.Ethylene 100 phr copolymer Picotac B Hydrocarbon resin 0-20 phr  Tufflo500 Hydrocarbon process oil 6-8 phr TMTD Tetramethylthiuram 0-1.8 phr  Peroxide Commodity 0-1 phr Celogen OT Expansion agent 0-1 phr Celogen765 Expansion agent 6-8 phr Bik-OT Expansion agent 0-4 phr

EXAMPLE 11

TRADE NAME COMPONENT AMOUNT SBR 1009 Styrene Butadiene 46.2 phr Primocor5990 Acid mod. Ethylene 30.1 phr copolymer SBR 1205 Styrene Butadiene23.1 phr Elvax 260 Ethylene Vinyl Acetate  100 phr RB 8101, 2Polybutadiene 76.9 phr 195 wax Clay treated wax 33.8 phr Resin 7312Hydrocarbon resin  3.8 phr QW200 Calcium Carbonate 61.5 phr Carbon blackOrganic Peroxide  3.8 phr TMTDT Tetramethylthiuram  5.4 phr disulfideCelogen OT Hyrazide 15.4 phr

Example 12 illustrates a moldable composition that was fabricated topossess the configuration illustrated in FIG. 6.

EXAMPLE 12

Material Name Supplier Quantity Wt % Material type SBR 1009 Ameripol-165 30.05 styrene butadiene Synpol rubber Nordel IP 4725 Dupont-Dow 15027.32 ethylene propylene rubber RT2730 (APAO) Huntsman 100 18.21 Polyalpha olefin MV2514 Exxon 50 9.11 Ethylene vinyl acetate GilsoniteMulti- Lexco 15 2.73 Hydrocarbon resin grade Carbon Black Cabot 2 0.36carbon black Regal 300 Celogen AZ180 Uniroyal 50 9.11 AzodicarbonamideSuperfine Sulfur Akrochem 5 0.91 sulfur Zinc Oxide Morton- 10 1.82 zincoxide Myers Industrene R Barton 2 0.36 stearic acid Solvents 549

The heat expandable composition of Example 12 was mixed in a labBakerPerkins mixer with dispersion blade. The following mix procedurewas utilized.

SBR rubber, EPDM rubber, Eva resin, and approximately ⅓ of the APAO wereblended. Blend was allowed to reach a temperature of 140° F., and mixuntil homogeneous. The mixer was stopped, and the Gilsonite, zinc oxide,stearic acid, blowing agent, sulfer, carbon black and the remainder ofthe APAO were added The composition was mixed until homogeneous, andattained a mix temperature of approximately 155° F. The mixedcomposition was extruded and die cut into the configuration shapeillustrated in FIG. 6.

The shaped article was located in opening of a steel 1×2 tubular framerail. The frame rail was introduced into a forced air oven chamber andexposed to a temperature of about 385 F for a period of twenty minutes.The composition expanded and filled the interior of the frame rail. Thecomposition adhered to the interior portion of the rails.

1-14. (canceled).
 15. A composition comprising a maleicanhydride-modified copolymer of ethylene and vinyl acetate, at least oneexpansion agent, at least one hydrocarbon resin, and at least one sulfurcontaining curing agent.
 16. The composition of claim 15 wherein atleast one expansion agent is a hydrazide.
 17. The composition of claim15 wherein at least one expansion agent is selected from the groupconsisting of p,p′-oxybis(benzenesulfonyl hydrazide) anddiphenylazide-4,4′-disulphohydrazides.
 18. The composition of claim 15wherein at least one hydrocarbon resin is selected from the groupconsisting of rosin esters, polyterpenes and C5 to C9 hydrocarbon andaromatically modified hydrocarbon resins.
 19. The composition of claim15 wherein at least one sulfur containing curing agent istetramethylthiuram disulfide.
 20. The composition of claim 15additionally comprising at least one processing oil.
 21. The compositionof claim 15 additionally comprising at least one supplemental polymerselected from the group consisting of ethylene acrylic acid copolymers,polybutadienes, ethylene vinyl acetate polymers, and ethylene propylenediene monomer polymers.
 22. The composition of claim 15 additionallycomprising at least one filler.
 23. The composition of claim 15 whereinthe maleic anhydride-modified copolymer of ethylene and vinyl acetatecomprises from about 50 to about 90 weight percent of the composition.24. The composition of claim 15 wherein the at least one hydrocarbonresin comprises from about 1 to about 15 weight percent of thecomposition.
 25. The composition of claim 15 wherein the at least oneexpansion agent comprises from about 1 to about 15 weight percent of thecomposition.
 26. The composition of claim 15 additionally comprising atleast one urea or modified urea.
 27. The composition of claim 15comprising both p,p′-oxybis(benzenesulfonyl hydrazide) and adiphenylazide4,4′-disulphohydrazide.
 28. The composition of claim 15comprising about 55 to about 84 weight percent of the maleicanhydrid-modified copolymer of ethylene and vinyl acetate, about 1 toabout 15 weight percent of the at least one expansion agent, said atleast one expansion agent being selected from the group consisting ofp,p′-oxybis(benzenesulfonyl hydrazide) anddiphenylazide-4,4′-disulphohydrazides, about 1 to about 15 weightpercent of the at least one hydrocarbon resin, and up to about 5 weightpercent of tetramethylthiuram disulfide.
 29. The composition of claim 28additionally comprising from about 5 to about 10 weight percent of atleast one supplemental polymer selected from the group consisting ofethylene acrylic acid copolymers and polybutadienes.
 30. The compositionof claim 28 additionally comprising at least one urea or modified urea.31. The composition of claim 28 additionally comprising at least onefiller.
 32. The composition of claim 28 wherein at least one hydrocarbonresin is selected from the group consisting of rosin esters,polyterpenes and C5 to C9 hydrocarbon and aromatically modifiedhydrocarbon resins.
 33. The composition of claim 28 additionallycomprising at least one peroxide.
 34. The composition of claim 28additionally comprising at least one processing oil.
 35. The compositionof claim 28 comprising both p,p′-oxybis(benzenesulfonyl hydrazide) and adiphenylazide 4,4′-disulphohydrazide.
 36. The composition of claim 28wherein at least one expansion agent is pretreated with a naphthenicbinder.
 37. The composition of claim 15, wherein said composition hasbeen injection molded.
 38. The composition of claim 15, wherein saidcomposition has been injection molded to form a self-retaining sealant.